GLdc/samples/zclip_triangle/main.c
2018-07-14 21:54:43 +01:00

99 lines
2.6 KiB
C

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "gl.h"
#include "glu.h"
#include "glkos.h"
/* A general OpenGL initialization function. Sets all of the initial parameters. */
void InitGL(int Width, int Height) // We call this right after our OpenGL window is created.
{
glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // This Will Clear The Background Color To Black
glClearDepth(1.0); // Enables Clearing Of The Depth Buffer
glDepthFunc(GL_LEQUAL); // The Type Of Depth Test To Do
glEnable(GL_DEPTH_TEST); // Enables Depth Testing
glShadeModel(GL_SMOOTH); // Enables Smooth Color Shading
glEnable(GL_TEXTURE_2D);
glMatrixMode(GL_PROJECTION);
glLoadIdentity(); // Reset The Projection Matrix
gluPerspective(45.0f,(GLfloat)Width/(GLfloat)Height,0.1f,100.0f); // Calculate The Aspect Ratio Of The Window
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
/* The function called when our window is resized (which shouldn't happen, because we're fullscreen) */
void ReSizeGLScene(int Width, int Height)
{
if (Height == 0) // Prevent A Divide By Zero If The Window Is Too Small
Height = 1;
glViewport(0, 0, Width, Height); // Reset The Current Viewport And Perspective Transformation
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0f,(GLfloat)Width/(GLfloat)Height,0.1f,100.0f);
glMatrixMode(GL_MODELVIEW);
}
/* The main drawing function. */
void DrawGLScene()
{
static GLfloat movement = 0.0f;
static GLboolean increasing = GL_TRUE;
if(movement > 10.0) {
increasing = GL_FALSE;
} else if(movement < -10.0f) {
increasing = GL_TRUE;
}
if(increasing) {
movement += 0.05f;
} else {
movement -= 0.05f;
}
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
glLoadIdentity(); // Reset The View
glDisable(GL_CULL_FACE);
glPushMatrix();
glTranslatef(0.0f, -1.0f, movement);
glBegin(GL_TRIANGLES);
glColor3f(1.0f, 0.0f, 0.0f);
glVertex3f(0.0f, 0.0f, -5.0f);
glColor3f(1.0f, 0.0f, 0.0f);
glVertex3f(-2.5f, 0.0f, 5.0f);
glColor3f(0.0f, 0.0f, 1.0f);
glVertex3f(2.5f, 0.0f, 5.0f);
glEnd();
glPopMatrix();
// swap buffers to display, since we're double buffered.
glKosSwapBuffers();
}
int main(int argc, char **argv)
{
glKosInit();
InitGL(640, 480);
ReSizeGLScene(640, 480);
while(1) {
DrawGLScene();
}
return 0;
}